

<template>
    <div class="main-clock">
        <div class="clock">

            <template v-for="i in 3" :key="i">
                <div class="flip">
                    <div class="digital front" data-number="0"></div>
                    <div class="digital back" data-number="1"></div>
                </div>
                <div class="flip">
                    <div class="digital front" data-number="0"></div>
                    <div class="digital back" data-number="1"></div>
                </div>
                <em class="divider" v-if ="i < 3">:</em>
            </template>
        </div>
    </div>
</template>

<script>
import { reactive, toRefs, onMounted } from "vue";


export default {
    name: "FlipClock",
    
    setup() {
        const state = reactive({

        });

        var Flipper = /** @class */ (function() {
            function Flipper(node, currentTime, nextTime) {
                this.isFlipping = false;
                this.duration = 400;
                this.flipNode = node;
                this.frontNode = node.querySelector(".front");
                this.backNode = node.querySelector(".back");
                this.setFrontTime(currentTime);
                this.setBackTime(nextTime);
            }
            Flipper.prototype.setFrontTime = function(time) {
                this.frontNode.dataset.number = time;
            };
            Flipper.prototype.setBackTime = function(time) {
                this.backNode.dataset.number = time;
            };
            Flipper.prototype.flipDown = function(currentTime, nextTime) {
                var _this =this;
                if(this.isFlipping) {
                    return false;
                }
                this.isFlipping = true;
                this.setFrontTime(currentTime);
                this.setBackTime(nextTime);
                this.flipNode.classList.add("running");
                setTimeout(function() {
                    _this.flipNode.classList.remove("running");
                    _this.isFlipping = false;
                    _this.setFrontTime(nextTime);
                }, this.duration);
            };
            return Flipper;
        }());

        var getTimeFromDate = function(date) {
            return date
                .toTimeString()
                .slice(0, 8)
                .split(":")
                .join("");
        };

        onMounted(() => {
            var flips = document.querySelectorAll(".flip");
            var now = new Date();
            var nowTimeStr = getTimeFromDate(new Date(now.getTime() - 1000));
            var nextTimeStr = getTimeFromDate(now);
            var flippers = Array.from(flips).map(function(flip, i) {return new Flipper(flip, nowTimeStr[i], nextTimeStr[i]);});
            setInterval(function() {
                var now =new Date();
                var nowTimeStr = getTimeFromDate(new Date(now.getTime() - 1000));
                var nextTimeStr = getTimeFromDate(now);
                for(var i=0; i < flippers.length; i++) {
                    if(nowTimeStr[i] === nextTimeStr[i]) {
                        continue;
                    }
                    flippers[i].flipDown(nowTimeStr[i], nextTimeStr[i]);
                }
            },1000);
        });

        return {
            ...toRefs(state),
        };
    },
};
</script>

<style lang="scss" scoped>

.main-clock
{
    display: flex;
    justify-content: center;
    align-items: center;
    height: calc(100vh - 96px) ;
}

.clock {
    display: flex;
  }
  
  /* 时钟的分隔 */
  .clock .divider {
    font-size: 66px;
    line-height: 102px;
    font-style: normal;
    color: rgb(51, 50, 50);
  }

  /* 时钟的卡片 */
  .clock .flip {
    position: relative;
    width: 60px;
    height: 100px;
    margin: 2px;
    font-size: 70px;
    font-weight: 700;
    line-height: 100px;
    text-align: center;
    background: rgb(46, 45, 45);
    border: 1px solid rgb(34, 33, 33);
    border-radius: 10px;
    box-shadow: 0 0 6px rgba(54, 54, 54, 0.5);
  }

  /* 时钟上的数字 */
  .clock .flip .digital::before, .clock .flip .digital::after {
    position: absolute;
    content: attr(data-number);
    left: 0;
    right: 0;
    color: white;
    background: rgb(51, 50, 50);
    overflow: hidden;
    -webkit-perspective: 160px;
            perspective: 160px;
  }

  /* 翻页前的数字 */
  .clock .flip .digital::before {
    top: 0;
    bottom: 50%;
    border-bottom: 1px solid #666;
    border-radius: 10px 10px 0 0;
  }

  /* 翻页后的数字 */
  .clock .flip .digital::after {
    top: 50%;
    bottom: 0;
    line-height: 0;
    border-radius: 0 0 10px 10px;
  }

  .clock .flip .back::before,
  .clock .flip .front::after {
    z-index: 1;
  }
  .clock .flip .back::after {
    z-index: 2;
  }
  .clock .flip .front::before {
    z-index: 3;
  }

  .clock .flip .back::after {
    -webkit-transform-origin: center top;
            transform-origin: center top;
    -webkit-transform: rotateX(0.5turn);
            transform: rotateX(0.5turn);
  }

  .clock .flip.running .front::before {
    -webkit-transform-origin: center bottom;
            transform-origin: center bottom;
    -webkit-animation: frontFlipDown 0.5s ease-in-out;
            animation: frontFlipDown 0.5s ease-in-out;
    box-shadow: 0 -2px 6px rgba(255, 255, 255, 0.3);
    -webkit-backface-visibility: hidden;
            backface-visibility: hidden;
  }

  .clock .flip.running .back::after {
    -webkit-animation: backFlipDown 0.6s ease-in-out;
            animation: backFlipDown 0.6s ease-in-out;
  }
  
  @-webkit-keyframes frontFlipDown {
    to {
      -webkit-transform: rotateX(0.5turn);
              transform: rotateX(0.5turn);
    }
  }
  
  @keyframes frontFlipDown {
    to {
      -webkit-transform: rotateX(0.5turn);
              transform: rotateX(0.5turn);
    }
  }

  @-webkit-keyframes backFlipDown {
    to {
      -webkit-transform: rotateX(0);
              transform: rotateX(0);
    }
  }
  
  @keyframes backFlipDown {
    to {
      -webkit-transform: rotateX(0);
              transform: rotateX(0);
    }
  }

</style>
